500g/1lb 1oz risotto rice, such as arborio or carnaroli
100ml/4fl oz white vermouth
knob of lactose free butter
1 lemon, juice only
2 zucchini (not too large), thinly sliced
100g/4oz parmesan, finely grated
small bunch fresh basil
Preheat the oven to 200C/390F/Gas 6.
Blanch the langoustine in a large saucepan of boiling salted water for 2-3 minutes. Drain and, when cool enough to handle, remove the heads and place them in a saucepan. Set the rest of the langoustine aside. Pour the chicken stock into the pan and heat gently.
Place the tomatoes in an ovenproof dish. Drizzle with olive oil and season with salt and freshly ground black pepper; roast for about 30 minutes, or until softened.
For the risotto, heat three tablespoons of olive oil in a large shallow pan or risotto pan. Add the rice, stirring to coat it in the oil. Stir in the vermouth. Cook until the liquid is absorbed.
Stir a knob of lactose free butter and a dash of lemon juice into the rice. Stir in the zucchini and a ladleful of hot stock. When the stock has been absorbed, remove the tomatoes from the vine and crush into the pan using the back of a spoon. Continue to add stock, allowing each ladleful to become absorbed until the risotto is creamy, but still retains a little bite.
Stir in nearly all the parmesan and half of the basil. Taste and adjust the seasoning with salt, pepper and lemon juice. Cover and set aside. Heat two tablespoons of olive oil in a frying pan, add the remaining langoustine and fry for two minutes.
Spoon the risotto into rings and arrange a langoustine on top of each serving. Finish with a sprinkling of parmesan and some torn basil leaves.